Using both resources listed above,
I was able to get Odoo up and running on a Raspberry Pi Model B+ and Raspberry
Pi 2. Odoo installed on the Raspberry Pi 2 is noticeably snappier than
the Model B+ (obviously), but I still think you could use the Model B+
(overclocked, turbo mode) if you have a small store and just want the ability
to print receipts and record sales.

STEPS TO INSTALLING ODOO ON A RASPBERRY PI

Step 1. Prepare your Raspbian
by ensuring the latest updates are installed and installing a bunch of packages
(not sure if all packages are required or not):

I had problems installing the Node
app Less as the Node.js packages available from the Raspbian are older.
The solution here is to install it manually, thanks to Nathaniel Johnson
(http://node-arm.herokuapp.com/).

wget
http://node-arm.herokuapp.com/node_latest_armhf.deb

sudo
dpkg -i node_latest_armhf.deb

sudo npm
install -g less less-plugin-clean-css

WKHTML2PDF from the Raspbian repository is too old for Odoo - you'll need to compile Qt5 and wkhtml2pdf. For now, I did without it knowing I will not be able to do some reports or reprint receipts.

Thank you for your work.With me pip install was alittle joker : I had to install the passlib a second time as the first seem to not have been correct. And the only way to install pyusb was to use "sudo pip install pyusb --allow-external pyusb"

I'm not experienced enough with the odoo v8 server to advise on that - I felt that there was a noticeable performance difference between the Raspberry Pi B+ and Raspberry Pi 2 with Odoo v9, and that was with only 1 user and using the web POS functions only.

I would say give it a go anyways and see if its do-able. You can always export your odoo instance to better hardware in the future. Good luck!

I just saw that my synology DS212+ NAS have odoo v8 in apps shop. From what I know it has a Marvel Kirkwood 88F6282 cpu.I don't find information or benchmark on "Kirkwood 88F6282 VS raspberry pi 2".Any clue?